The failure to work for justice means “there can be no real peace and harmony,” the Pope said, according to Vatican Radio.

Everyone should promote and practice “justice with truth and love” while contributing to “integral human development,” he added. This means an end to “egotism, individualism, and group interests at every level.”

The Pope reflected on the relevance of the 1963 encyclical “Pacem in Terris” – or “Peace on Earth – written by Bl. John XXIII, who will be canonized next spring.

Although the encyclical was written near the height of Cold War tensions between the United States and Russia, it remains “extremely contemporary,” Pope Francis said.

Despite “the fall of walls and barriers, the world continues to need peace,” he told participants in a three-day Vatican conference marking the encyclical’s 50th anniversary.

The conference drew participants from the U.N., the Council of Europe, the African Union, the Organization of American States, and Catholic universities and institutions, Vatican Radio reports.

Pope Francis said the encyclical reminds Christians that peacemaking is based in mankind’s “divine origin.” This common origin means every human being shares a common dignity that they must “promote, respect and safeguard always.”

He urged more efforts to provide access to food, water, shelter, health care and education. He also emphasized the need for everyone to have the possibility “to form and support a family.”

“On this depends an enduring peace for everyone,” Pope Francis said.

He also noted that during the 1962 Cuban Missile Crisis, Pope John XXIII called for peace, attempting to orient the international debate towards the virtues of “dialogue, listening, patience, respect of the other, sincerity and even an openness to reconsidering one’s own opinion.”

Pope Francis encouraged his audience to reflect on “Pacem in Terris” as they respond to challenges to peace today, including those in the realms of education, lack of access to resources, ethical problems in biological research, arms races, and the mass media’s “impact on consciences.”

The current economic crisis is “inhuman” and “a grave symptom of the disrespect for man and for (the) truth with which governments and citizens make decisions,” he added.

The Holy Father briefly mentioned current events, voicing his sorrow for the hundreds of African refugees dead or missing after the recent sinking of a refugee-laden boat off the southern Italian island of Lampedusa.

“It is a shame!” he said. “Let us pray together to God for those who have lost their lives: men, women, children, for the families and for all the refugees.”